Originally Posted by
berlinonaut
How would ETRO 507 wheels be not standard components? ETRO 507 IS a standard... Just because you probably do not get them in the supermarket around the corner? Then there is a problem: If you consider everything that is not identical to all the other bikes around to be "non standard" (and thus a downside) but on the other hand want a bike that massively differs from all the other bikes around in terms that it should i.e. be lighter and have bigger wheels and still fold very compact but at the same time is identical to all the other bikes around you end up in a catch 22....
If you consider any ETRTO size to be standard, then yes ETRTO 507 is a standard component.
But if you look at the amount of road bikes using ETRTO 507 wheels, then its not (there is ETRTO 520 for junior or woman road bikes).
And ETRTO 507 40mm wide or less tires aren't standard at all.
Having several bikes with ETRTO 406 wheels and having used an ETRTO 520 wheeled bike, I am absolutely not convinced of the benefit of using ETRTO 507 wheels.
The only thing I am sure is that it drastically reduces the choice of tires (and tires a crucial for the bike performances, the same problem exists for the Brompton, no high end high performances folding tires unless the Schwalbe One presented on the 2019 CHPT3 become available as spare parts), it makes the bike bigger (an Helix with ETRTO 406 wheels would be smaller) and it increases the weight (an Helix with ETRTO 406 wheels would weight less).
In your list of Brompton improvements, you forgot that the wheelbase of the Brompton was increased what changed the behavior of the bike.